Enteroviruses cause Type 1

More than 60% of children who died within a year of Type 1 Diabetes diagnosis had enteroviruses in their pancreas.

... a common family of viruses (enteroviruses) may play an important role in triggering the development of diabetes, particularly in children. These viruses usually cause symptoms similar to the common cold, or vomiting and diarrhoea. However, the team has now provided clear evidence that they are also found frequently in the pancreas of people who develop diabetes.

It is accepted that children who develop type 1 diabetes inherit a genetic susceptibility to the disease, but studies of identical twins have shown that when one twin has the disease, the other twin will only have approximately a 40 per cent chance of developing diabetes – suggesting that factors additional to inheritance are also involved.

It has long been speculated that viruses might play a role in causing type 1 diabetes by infecting the beta cells of the pancreas. This new research, which has made use of unique source material collected in Glasgow, is the first to provide evidence supporting this theory in such a large number of pancreases from young people recently diagnosed with the disease. It has revealed that more than 60 per cent of the organs contained evidence of enteroviral infection of the beta cells. By contrast, infected beta cells were hardly ever seen in tissue samples from 50 children without the condition.

The new research suggests that enteroviral infection of the beta cells in children with a genetic disposition to type 1 diabetes may initiate a process whereby the body's immune system identifies beta cells as 'foreign' and rejects them, as it would a transplanted organ. [emphasis mine]